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Thermal Relaxation in One-Dimensional Self-Gravitating Systems

Junichiro MAKINOgif
Department of Systems Science, College of Arts and Sciences,
University of Tokyo, Tokyo 153-8902


In this paper, we study the thermal relaxation in the one-dimensional self-gravitating system, or the so-called sheet model. According to the standard argument, the thermal relaxation time of the system is around , where N is the number of sheets and is the crossing time. It has been claimed that the system does not reach the thermal equilibrium in this thermal relaxation timescale, and that it takes much longer time for the system to reach true thermal equilibrium.

We demonstrate that this behavior is explained simply by the fact that the relaxation time is long. The relaxation time of sheets with average binding energy is , and that of sheets with high energy can exceed . Thus, one needs to take the average over the relaxation timescale of high-energy sheets, if one wants to look at the thermal characteristic of these high energy sheets.

Jun Makino
Tue Mar 16 18:39:24 JST 1999